Material screening and feeding mechanism



April 3, 1945. E, A. GLYNN EIAL MATERIAL SCREENING AND FEEDING MECHANISM Filed Feb. 8. 1943 2 Sheets-Sheet 1 Edwin H Glynn Stanley Marvin April 3, 1945. E. A. GLYNN ET AL MATERIAL SCREENING AND FEEDING MECHANISM 2 Sheets-Sheet 2 Filed Feb. s, 1945 Patented Apr. 3, 1945 MATERIAL SGR'EENING AND FEEDIN MECHANISM Edwin A. Glynn and Sta assignors to Supe fdrnia, Lodi, Calif,

V meyfMarnn, Lcai,;oa 1ir., r Mold Corporation of Call- Application February 8, 1943, Serial N6. 475, 090 2 Claims. (cream-284) This invention relates in general to a material screening and feeding mechanism, and in particular is directed to a mechanism for this purpose especially designed for use in connection with the screening and feeding of dry placer mineral in the course of dry concentrating thereof to recover the values.

One of-the objects of this invention is to provide a material screening and feeding mechanism which includes an axially elongated rotary screen having unique means associated therewith to thoroughly mix the material whichpasses through the screen, and to then feed such materialdownwardly from the mechanism in evenly distributed relation longitudinally of thescreemas isinec'essary to accomplish equality of feed of the screened and mixed material to a longitudinal bank of dry concentrating units or tables which the machine includes below the screen.

Another object of the present invention is to provide a material screening and feeding mechanism which comprises an elongated rotary screen supported on a suitable frame in driven and slightly-downwardly sloping relation, a helical screw'mou'ntedon and surrounding the screen in outwardly projecting relation, and a material receiving trough below thescreen in which the lower portion of the helical screwruns, whereby to mix screened material in the trough and to feed said material evenly over a longitudinal spillway formed by one top edge of said trough. A further objectof this" invention is to provide a material screening and feeding mechanism, as

' in the precedingparagraph, in which the trough is relatively shallow but generally V-shaped in 5 cross section, the side of said trough which includes said spillway forming top edge comprising initially separate longitudinal plates, and means adjustably mounting the uppermost one of said plates whereby the spillway forming edge thereof may be selectively inclined downwardly from adjacent the intake of the screen so as to regulate the spill over said spillway to a substantially equal amount throughout its length.

A still further object of the invention is to construct the material receiving trough, which is disposed below the rotary screen, so that one side of said trough, while normally closing along the bottom edge with the corresponding edge of the other side of the trough, is mounted for lateral separating movement whereby to open a. longitudinal gap in the bottom of the trough and permit discharge of all material therefrom.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly .eilective for the :purpose =for whichitis designed.

These objects we accomplish by means ofsuch structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the-drawings similar characters'of reference indicate corresponding parts'iin the several views: Figure l is a side elevationrof the mechanism. Figure 2 is a plan view ofthe same with the rotary. screen removed. v ,Figure 3.;is an enlarged crosssection on line 3--3-of Fig.1.

= Referring nowmore particularlyito the characters of reference on the drawings, the mechanism 'comprisesian 'elongateii rotary screen I .disposed with its axis at a slight .downwardslope from the intake end of thescreen; vsaid screen being rotatably supported by a-bearing. 2 andarollers 3-.on a suitable frame F which includes transversely-spacedend legs 4. Material tobe screened is fed into the upper end of the rotary screen by 'suitabl-emeans such as a chute 5.

A helical .screw .intheform of anoutwardly projecting vane 6 secured exteriorly on the rotary screen i and extends from end :to end thereof on ar'elatively long pitch; said vane being of substantial width radially :of therotary screen.-

Downwardly converging, rtransverse frame members I support longitudinal plates :8 and :9 which include downwardly extending edge flanges 10- which seat on said-frame members 1;sa'id :plates -8 normally engaging along their lower or bottom edges and diverging upwardly therefrom to form a shallow but generally V-shaped trough- II, which is inclined to correspond to the slope of the screen. The flanges ID of the plate 9 are fixed to the corresponding and supporting frame members 1, while the flanges I 0 of the plate 9 slidably seat on the corresponding frame member 1 whereby to permit of upward sliding movement of plate 9 in a lateral direction. The purpose of movably mounting the plate 9 is so that the same may be shifted laterally to open a gap in the bottom of the trough and consequent emptying of the latter when necessary.

Such lateral movement of the plate 9 is accomplished through the medium of a plurality of pivotally mounted links l2 connected between the uppermost flange ID of plate 9 and cranks I 3 fixed on a. longitudinally extending shaft l4 suitably journaled on the frame to one side of and parallel to the trough. Adjacent one end the shaft I4 is fitted with a radial actuating lever l5.

It will be seen that with outward swinging movement of lever M the plate 9 will be drawn upwardly to open a gap between adjacent lower taohed to the adjacent frame members 1 by.

means of U bolts [8. The upper edge of plate 16, indicated at S, forms a spillway, the downward inclination of which, longitudinally of the machine, may be altered by adjusting the plate l6 by means of the U bolts I8. In other words, the plate Hi can be set so that the downward inclination of edge S is greater than the corresponding downward inclination of the axis of the rotary screen, and which may be desirable as will hereinafter appear.

In operation the plate 9 is normally closed with the plate 8, and as the dry placer material is fed into the rotary screen I from the chute 5 the portion thereof which passes through the screen falls into the trough, while the residual portion which does not pass through the screen discharges from the lower end thereof and is carried away by a suitable conveyor (not shown).

The rotary screen revolves in the direction shown by the arrow in Fig. 3, and the pitch of the helical screw 6 is such that with rotation of the screen the lower portion of the screw tends to move material in the trough up the side thereof comprised by plates 8 and I6 and to discharge said material over the spillway formed by upper edge S of the latter plate. Also with such movement of the material by the screw, an effective mixing action is obtained, which assures a proper admixture of the fines with the remainder of the screened material before the latter is discharged over the edge S and falls downwardly for treatment at the dry concentrating units or tables (not shown) but which are disposed therebelow.

By adjusting the degree of inclination of the spillway S relative to the inclination of the rotary screen the amount of material flowing over the spillway may be regulated so that at all points in the length thereof the amount of spilling material is equal. There is a tendency for a greater portion of the screened material to enter the trough from the screen adjacent the upper end portion of the latter, and thus if the spillway paralleled the screen axis, a greater amount would flow over the upper end portion of the spillway than at other points therealong. To overcome thi the plate It is adjusted so that the spillway 5 has a greater degree of inclination than the screen axis, and this causes material which would otherwise spill adjacent the'upper end portion to remain in the trough for discharging over spillways at a lower point.

From the foregoing description it will be readily seen that we have produced such a device as substantially fulfills the objects of the invention as set forth herein,

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thu described our invention, what we claim as new and useful and desire to secure by Letters Patent is: A

l. A material screening and feeding mechanism comprising a rotary screen having a helical screw on the outside thereof, a frame assembly disposed beneath the screen in supporting relation thereto, and a material receiving trough supported by said frame assembly lengthwise of and below said screen, the lower circumferential portion of said screen and screw running in the trough; the frame assembly including a plurality of V-shaped frames disposed in side by side but spaced relation, and said trough comprising a pair of longitudinally extending side plates disposed in diverging relation from normally engaged lower edges, downwardly extending longitudinal flanges on the edges of said plates seating on said frames, another plate disposed lengthwise of one of said side plates, partially lapping the upper edge portio of the latter and extending laterally at an upward incline, a down-turned flange on the upper edge of said other plate seating on said frames, and means adjustably securing said other plate in connection with said frames.

2. A material feeding and screening mechanism as in claim 1 in which said last named means comprises inverted U-shaped bolt units fixed on and projecting from the downturned flange on said other plate in straddling relation to said V-shaped frames.

EDWIN A. GLYNN. STANLEY MARVIN. 

